If there was a 1099-C received for this tax year, you will need to account for it on this tax return. Otherwise you will need to amend the return later or face an IRS notice that will charge additional interest and penalties.
There are exceptions to canceled debt income that may keep this from being taxable income (or example if you were insolvent when the debt was cancelled). If there are issues with having adequate documentation for being insolvent, I would recommend extending (so you can gather all the information you need) rather than waiting to report the income later.
